Aspects of the subject disclosure may include, for example, a system having a plurality of transmitters for launching, according to a signal, instances of first electromagnetic waves having different phases to induce propagation of a second electromagnetic wave at an interface of a transmission medium, the second electromagnetic wave having a non-fundamental wave mode and a non-optical operating frequency, wherein the plurality of transmitters has a corresponding plurality of antennas. A reflective plate is spaced a distance behind the plurality of antennas relative to a direction of the propagation of the second electromagnetic wave. Other embodiments are disclosed.